Camera system, lens unit and accessory device

ABSTRACT

A lens unit has a photographing lens, and is secured removably to a camera main body. An accessory conversion lens device is settable on the lens unit. The lens unit includes a reception unit for receiving accessory device data from the conversion lens device. A determiner checks propriety of the conversion lens device according to accessory device data received by the reception unit, and produces checking information. A transmission unit transmits the checking information to the main body. Specifically, the lens unit has an image pickup element. Also, the conversion lens device includes an RFID tag for storing the accessory device data. The reception unit includes an RFID tag reader for wireless reception. Also, the main body includes an LCD panel to display for outputting alarm information. A main body controller drives the LCD panel if the checking information represents lack of the propriety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a camera system, lens unit andaccessory device. More particularly, the present invention relates to acamera system in which a lens unit and other elements can be combinedwith ensured propriety, and such a lens unit and accessory device.

2. Description Related to the Prior Art

A camera system known in the art is a combination of a lens unit and acamera main body. The lens unit accommodates a photographing lens. Themain body supports the lens unit removably. It is possible to load oneof the main body and the lens unit with an accessory device, for examplean electronic flash unit, a conversion lens device, and the like. It isknown to mount the accessory device between the main body and the lensunit, for example a rear converter for changing a focal length orsubject distance.

There occurs a change in the aperture stop or focal length betweenphotographing with the accessory device and photographing without theaccessory device, such as a conversion lens device and rear converter.If a type of the accessory device is not suitable for the lens unit orthe camera main body, there occurs a problem in impropriety in theautomatic exposure control or automatic focus adjustment.

JP-A 6-027515 and JP-A 2002-072328 disclose a camera system in which thelens unit has CPU, and the CPU, upon setting the accessory devicebetween the lens unit and the camera main body, detects existence andtype of the accessory device to supply the main body with type data ofthe accessory device by transmission. U.S. Pat. No. 6,707,992(corresponding to JP-A 2002-258380) discloses a camera system in which arear converter as the accessory device is settable between the lens unitand the main body. An intermediate communicating terminal is disposed inthe rear converter for transmission between the lens unit and the mainbody. Type data of the rear converter is transmitted to the main body intransmitting type data of the lens unit to the main body. U.S. Pat. No.6,738,574 (corresponding to JP-A 2003-228114) suggests a camera systemin which a determiner is incorporated in the main body, and compares theaccessory type data with the camera main body type data upon setting theaccessory device on the main body, to check propriety between the mainbody and the accessory device.

In the constructions disclosed in those documents, type data of theaccessory device and the lens unit are transmitted to the camera mainbody. The determiner in the main body checks propriety of the accessorydevice or the lens unit. If the main body does not have the determiner,propriety cannot be checked. No known camera system is successful indetermining propriety of the accessory device of the lens unit.

SUMMARY OF THE INVENTION

In view of the foregoing problems, an object of the present invention isto provide a camera system in which a lens unit and other elements canbe combined with ensured propriety, and such a lens unit and accessorydevice.

In order to achieve the above and other objects and advantages of thisinvention, a camera system is provided, including a lens unit having aphotographing lens, and a camera main body on which the lens unit issecured removably, wherein an accessory device is settable on a selectedone of the main body and the lens unit. In the camera system, the lensunit includes a first reception unit for receiving accessory device datafrom the accessory device. A determiner checks whether the accessorydevice is appropriate for the lens unit or the main body according toaccessory device data received by the first reception unit, and produceschecking information. A transmission unit transmits the checkinginformation. The main body includes a second reception unit forreceiving the checking information from the lens unit.

The accessory device data is accessory type data of a type of theaccessory device.

The main body includes an alarm device for outputting alarm information.A main body controller drives the alarm device if the checkinginformation represents that the accessory device is inappropriate.

The second reception unit is connected with the transmission unit byconnection between contacts, and detects whether the lens unit is set onthe main body.

The alarm device includes a display panel for visibly outputting thealarm information.

The first reception unit further receives camera main body data from themain body. The determiner checks whether a combination of the lens unit,the accessory device and the main body is appropriate.

The accessory device includes a first RFID tag for storing the accessorydevice data. The first reception unit includes an RFID tag reader forwireless reception.

The main body includes a second RFID tag for storing camera main bodydata. The RFID tag reader further reads the main body data from thesecond RFID tag.

The accessory device is a conversion lens device or a flash device.

In one aspect of the invention, a lens unit has a photographing lens,and is secured removably to a camera main body to constitute a camerasystem, wherein an accessory device is settable on the camera system. Areception unit receives accessory device data from the accessory device.A determiner checks whether the accessory device is appropriate for thecamera system according to accessory device data received by thereception unit, and produces checking information. A transmission unittransmits the checking information to the main body.

Furthermore, an image pickup element photographs an object image byreceiving light from the photographing lens.

The accessory device includes an RFID tag for storing the accessorydevice data. The reception unit includes an RFID tag reader for wirelessreception.

In another aspect of the invention, a camera system includes a lens unithaving a photographing lens, a camera main body on which the lens unitis secured removably, and an accessory device secured between the mainbody and the lens unit. In the camera system, the accessory deviceincludes a first reception unit for receiving lens unit data from thelens unit. A determiner checks whether the lens unit is appropriateaccording to lens unit data received by the first reception unit, andproduces checking information. A transmission unit transmits thechecking information. The main body includes a second reception unit forreceiving the checking information from the accessory device.

The main body includes an alarm device for outputting alarm information.A main body controller drives the alarm device if the checkinginformation represents that the accessory device is inappropriate.

The second reception unit is connected with the transmission unit byconnection between contacts, and detects whether the accessory device isset on the main body.

The alarm device includes a display panel for visibly outputting thealarm information.

The first reception unit further receives camera main body data from themain body. The determiner checks whether a combination of the lens unit,the accessory device and the main body is appropriate.

The accessory device includes a first RFID tag for storing the lens unitdata. The first reception unit includes an RFID tag reader for wirelessreception.

The main body includes a second RFID tag for storing camera main bodydata. The RFID tag reader further reads the main body data from thesecond RFID tag.

The lens unit includes a first communication contact. The accessorydevice includes a second communication contact, connected with the firstcommunication contact by securing the lens unit, for detecting whetherthe lens unit is set.

The lens unit further includes an image pickup element for photographingan object image by receiving light from the photographing lens.

The accessory device is an image shake correcting device.

In still another aspect of the invention, an accessory device is securedbetween a camera main body and a lens unit having a photographing lensand being secured to the main body removably. A reception unit receiveslens unit data from the lens unit. A determiner checks whether the lensunit is appropriate according to lens unit data received by thereception unit, and produces checking information. A transmission unittransmits the checking information to the main body.

The lens unit includes an RFID tag for storing the lens unit data. Thereception unit includes an RFID tag reader for wireless reception.

BRIEF DESCRIPTION OF THE DRAWINGS

The above objects and advantages of the present invention will becomemore apparent from the following detailed description when read inconnection with the accompanying drawings, in which:

FIG. 1 is a perspective view illustrating a camera system;

FIG. 2 is a block diagram illustrating the camera system

FIG. 3 is a flow chart illustrating checking of propriety in the camerasystem;

FIG. 4 is a block diagram illustrating another preferred camera systemwith a flash device;

FIG. 5 is a flow chart illustrating checking of propriety in the camerasystem;

FIG. 6 is a block diagram illustrating one preferred camera system withan image shake correcting device;

FIG. 7 is a flow chart illustrating checking of propriety in the camerasystem;

FIG. 8 is a block diagram illustrating still another preferred camerasystem in which a second RFID tag is added;

FIG. 9 is a flow chart illustrating checking of propriety in the camerasystem.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S) OF THE PRESENTINVENTION

In FIG. 1, a camera system 10 of the invention is illustrated. A cameramain body 11 of the camera system 10 is loaded with a lens unit 12 in aremovable manner. Also, a conversion lens device or converter 13 asaccessory device or attachment is used in combination, and settable onthe front of the lens unit 12.

A photographing lens 14 appears in the front of the lens unit 12. A lensunit coupling mechanism 15 is disposed on the rear of the lens unit 12.Bayonet lugs 16 are included in the lens unit coupling mechanism 15.Communication contacts 16 a lie on the surface of the bayonet lugs 16for connection. A CCD 17 as image pickup element is incorporated in thelens unit 12, and photographs an object image by receiving object lightfocused by the photographing lens 14.

A lens mount mechanism 18 is disposed on a front surface of the mainbody 11. Bayonet channels 19 are defined in the lens mount mechanism 18.To load the main body 11 with the lens unit 12, the bayonet lugs 16 arepositioned in and pressed into the bayonet channels 19. The lens unit 12is rotated in the clockwise direction and become fitted on the main body11. Note that the lens unit 12 is an interchangeable type of lens, andselected from predetermined examples. The examples include a type with adifferent focal length of the photographing lens 14, a type with adifferent number of pixels of the CCD 17, a type for monochromaticphotography, a type enabling infrared photography, and the like.

A lock pin 20 is disposed in the lens mount mechanism 18. When the mainbody 11 is loaded with the lens unit 12, a hole (not shown) formed inthe lens unit coupling mechanism 15 receives the lock pin 20 to blockrotation of the lens unit 12. The lens unit 12 is kept secured on themain body 11 without drop. Furthermore, a cover lid 21 is disposed onthe lens mount mechanism 18 and biased in a forward direction with aspring, and prevents dust from entry in the main body 11 when the lensunit 12 is not loaded.

An unlocking button 22 is disposed near to the lens mount mechanism 18.When the unlocking button 22 is depressed while the lens unit 12 is seton the main body 11, then the lock pin 20 moves in the backwarddirection, to release from the hole. The lens unit 12 can be removedfrom the main body 11 by rotating the lens unit 12 and depressing theunlocking button 22.

A flash light source 24 is disposed near to the lens mount mechanism 18.A release button 25 and a selector wheel 26 are disposed on an uppersurface of the main body 11. The release button 25 is depressible forphotographing. The selector wheel 26 is rotationally shifted for settinga selected one of a photographing mode and a playback mode. A notifyingLCD 33 as display panel and a power switch (not shown) are disposed onthe rear of the main body 11.

An RFID tag or IC tag 50 (See FIG. 2) is incorporated in the conversionlens device 13, and stores information such as accessory type data.Also, an RFID tag coil 28 is included in the RFID tag 50, and disposedon the rear. An RFID tag reader 43 as first reception unit is includedin the lens unit 12, and reads the accessory type data of a radio wavefrom the RFID tag 50. See FIG. 2. A tag reader coil 31 in the RFID tagreader 43 is disposed on the front.

Note that any of various types of the conversion lens device 13 may beused, for example a wide conversion lens for wide-angle photography, atelephoto conversion lens for telephoto photography, and a macro lensfor close-up photography.

Arrangement of circuits in the camera system 10 is described now. InFIG. 2, the main body 11 includes a main body controller 30, an internalmemory 29, an image processor 32, the LCD 33 as a display, a powersource control unit 34, a battery 35, contacts 36, a media controller37, and a transmission/reception unit 38 as second reception unit orcommunication interface.

The internal memory 29 includes a ROM and RAM. The ROM stores controlprogram for controlling the elements in the main body 11 and the lensunit 12. The RAM stores data for tasks in a temporary manner. The mainbody controller 30 controls operation of photographing according to thecontrol program.

The image processor 32 processes image data from the lens unit 12according to various steps of image processing. The LCD 33 displays arecordable image and patterns for inputs, and also a live image. Thepower source control unit 34 is connected with the battery 35, suppliesthe circuits in the main body 11 with power by converting an outputvoltage of the battery 35 into a predetermined voltage, and alsosupplies the lens unit 12 with power through the contacts 16 a and 36.

The contacts 36 are positioned in the lens mount mechanism 18, andbecome connected with the contacts 16 a of the lens unit 12 upon settingthe lens unit 12 on the lens mount mechanism 18. A memory card 39 isremovably loaded in the main body 11, and accessed by the mediacontroller 37 for reading and writing. The transmission/reception unit38 is a serial driver, controlled by the main body controller 30, andtransmits data to or receives data from the lens unit 12 by converting aparallel signal to a serial signal.

Arrangement of circuits in the lens unit 12 is described next. The lensunit 12 includes a controller 40, the CCD 17, a data processor 41, thecontacts 16 a, a memory 42, the RFID tag reader 43, a determiner 44, anda transmission/reception unit 45 or communication interface.

The controller 40 controls various elements in the lens unit 12. The CCD17 photographs an object image by receiving object light focused by thephotographing lens 14. The data processor 41 subjects image data fromthe CCD 17 to various processes, for example elimination of electricnoise, amplification, A/D conversion and the like. The memory 42 storesa control program to control elements in the lens unit 12. Thecontroller 40 runs the control program and controls the elements. Thecontroller 40 is connected with the main body controller 30 by thetransmission/reception unit 45 and the contacts 16 a and 36, andcontrolled by the main body controller 30.

The RFID tag reader 43 for wireless reception reads the accessory- typedata from the RFID tag 50 in the conversion lens device 13. The RFID tagreader 43 has the tag reader coil 31. The tag reader coil 31 includes anelectromagnetic coil 31 a and a receiver coil 31 b. The electromagneticcoil 31 a generates electromotive force in the RFID tag 50. The receivercoil 31 b receives the accessory type data output by the RFID tag coil28 in the RFID tag 50 wirelessly. The coils 31 a and 31 b extend on thecylindrical shape of the lens unit 12 and outside the photographing lens14.

The determiner 44 stores a reference data table for data of proprietywith plural accessory devices, and evaluates the obtained accessory typedata from the RFID tag reader 43 by referring to the data table, tocheck propriety of the lens unit 12. If no adjustment of focus ispossible even upon setting the conversion lens device 13, then a resultof the check is impropriety.

The transmission/reception unit 45 is controlled by the controller 40,and transmits data to and receives data from the main body 11. After theaccessory device is found appropriate for the lens unit 12 by thedeterminer 44, then data of the propriety as a result is transmitted bythe transmission/reception unit 45 to the main body 11.

Electric arrangement of the conversion lens device 13 is described now.The RFID tag 50 is included in the conversion lens device 13. The RFIDtag 50 includes a data storage region 51, the RFID tag coil 28 and acontrol region 52. The data storage region 51 stores accessory type dataassociated with the conversion lens device 13. The RFID tag coil 28wirelessly outputs a radio wave of the accessory type data in the datastorage region 51. The control region 52 reads the accessory type datafrom the data storage region 51, and causes the RFID tag coil 28 totransmit the accessory type data to the exterior. Elements including thedata storage region 51, the RFID tag coil 28 and the control region 52are arranged around the lens element. The RFID tag coil 28 is formed toextend on the peripheral form of the conversion lens device 13. Notethat any of various suitable types of the RFID tag 50 may be used, forexample, μ-Chip (trade name, manufactured by Hitachi Ltd.) having a sizeof 0.4 mm and including an antenna.

When the conversion lens device 13 comes near to the lens unit 12 priorto attachment to the lens unit 12, a radio wave is emitted by theelectromagnetic coil 31 a, to generate electromotive force in the RFIDtag coil 28 by electromagnetic induction. The RFID tag 50 is driven bythe electromotive force. Accessory type data is wirelessly output by theRFID tag coil 28. The receiver coil 31 b of the RFID tag reader 43receives the accessory type data.

The operation of the camera system 10 is described with reference toFIG. 3. When the lens unit 12 is set on the main body 11, at first thecontroller 40 checks as to whether the conversion lens device 13 is setor not. To this end, whether the accessory type data is received or notis checked by use of the RFID tag reader 43.

If no conversion lens device 13 is found by the controller 40, then thecontroller 40 causes the transmission/reception unit 45 to transmit dataof lack of the accessory device to the main body 11 through the contacts16 a and 36. The main body controller 30 causes thetransmission/reception unit 38 to receive the data, and controls theoperation of photography normally.

If the conversion lens device 13 is found set on the lens unit 12, thenthe determiner 44 evaluates the received accessory type data and checkspropriety of the conversion lens device 13. If lack of the propriety isdetermined by the determiner 44, then the controller 40 controls thetransmission/reception unit 45 to send data of the lack of the proprietyto the main body 11.

When the transmission/reception unit 38 at the main body controller 30receives the data of being not appropriate, then the main bodycontroller 30 causes the LCD 33 to display a warning message ofimpropriety between the lens unit 12 and the conversion lens device 13.Note that other messages may be indicated besides the warning message,for example, a message that restriction will occur in the performance ofphotographing.

If the conversion lens device 13 is found appropriate, then thecontroller 40 causes the transmission/reception unit 45 to transmit dataof being appropriate to the main body 11. After this, the main bodycontroller 30, upon receiving the data of being appropriate at thetransmission/reception unit 38, allows the camera system to photographan image normally without restriction.

Despite the present embodiment, an accessory device of the invention maybe other than the conversion lens device 13, for example, an electronicflash device. The flash device can be a type settable on the lens unit12, or may be a type settable on the main body 11.

The first embodiment has been described heretofore, the propriety beingchecked between the accessory device and the lens unit 12. Anotherpreferred embodiment is now described, in which propriety is checkedbetween the accessory device, the lens unit 12 and the main body 11.

In FIG. 4, a camera system 60 includes a camera main body 61 and a lensunit 62. The lens unit 62 is removably fitted on the main body 61 in asimilar manner to the camera system 10. A flash device 63 as accessorydevice or attachment is set on the outside of the lens unit 62removably.

An RFID tag or IC tag 65 is incorporated in the main body 61. Cameramain body type data particularly associated with the main body 61 isstored in the RFID tag 65. As the RFID tag 65 is structurally the sameas the RFID tag 50, no further description is added. Also, the main body61 is structurally the same as the main body 11. Elements similar tothose of the above embodiments are designated with identical referencenumerals.

Unlike the lens unit 12, a determiner 66 is incorporated in the lensunit 62 in a manner in place of the determiner 44. Elements similar tothose of the lens unit 12 are referred to with reference numerals.

The flash device 63 includes a flash circuit board 67 and an RFID tag orIC tag 68. The RFID tag 68 has a data storage region which stores theaccessory type data assigned to the flash device 63 as type data.

The RFID tag reader 43 in the lens unit 62 receives the camera main bodytype data from the RFID tag 65, and receives accessory type data fromthe RFID tag 68. A reference data table is stored in the determiner 66and is information of propriety of the accessory device and the mainbody 61. The determiner 66 evaluates propriety between the main body 61,the lens unit 62 and the flash device 63 by referring to the referencedata table, camera main body type data and accessory type data.

The operation of the camera system 60 is described by referring to FIG.5. When the lens unit 62 is set on the main body 61, the controller 40checks whether the flash device 63 is set or not. To this end, whetherthe accessory type data is received or not is checked by use of the RFIDtag reader 43.

When no flash device 63 is found by the controller 40, then thecontroller 40 causes the transmission/reception unit 45 to transmit dataof lack of the accessory device to the main body 61 through the contacts16 a and 36. The transmission/reception unit 38 at the main bodycontroller 30 receives the data, before normal control of operation.

If the flash device 63 is found set on the main body 61, then thedeterminer 66 checks whether the flash device 63 is appropriate for thelens unit 62 according to the accessory type data being received.

If impropriety with the lens unit 62 is found, the controller 40 causesthe transmission/reception unit 45 to transmit data of impropriety tothe main body 61. The main body controller 30, upon receipt of the dataof impropriety at the transmission/reception unit 38, causes the LCD 33to indicate a warning message of impropriety between the lens unit 62and the flash device 63.

A message of restricting performance of photography can be displayedwithout warning message. For example, it is possible to allowphotography even when the flash device 63 is found not appropriate, withrestriction in the zooming. This is for preventing lens vignetting whenthe lens unit 62 is zoomed to the forward position. Also, it is possibleautomatically to preflash for photographing even the flash device 63 isfound not appropriate. This is to prevent red-eye phenomena in thecombined use of the lens unit 62 and the flash device 63. In relation tothe flash device 63, it is possible for the transmission/reception unit45 to transmit control information of the flash device 63 to the mainbody 61 together with the data of impropriety.

If the flash device 63 is found appropriate for the lens unit 62, thenthe determiner 66 evaluates the camera main body type data and the lensunit type data, and checks as to propriety of the flash device 63 withthe main body 61.

If the flash device 63 is found not appropriate for the main body 61,then the data of the impropriety is transmitted to the main body 61.Upon receiving this, the main body controller 30 causes the LCD 33 todisplay a warning message of impropriety between the main body 61 andthe flash device 63. Note that other messages may be indicated besidesthe warning message, for example, a message that restriction will occurin the performance of photographing.

If the flash device 63 is found appropriate for the main body 61, thenthe controller 40 causes the transmission/reception unit 45 to transmitthe data of the propriety to the main body 61. Then the main bodycontroller 30, upon receiving the data of being appropriate at thetransmission/reception unit 38, allows the camera system to photographan image normally without restriction.

In the above embodiments, the accessory device is fitted on the lensunit. However, an accessory device of the invention can be loaded on thecamera body. Furthermore, accessory devices may be electrically movabletilting heads, outer monitor display or the like in addition to theconversion lens device 13 or the flash device 63.

An accessory device may be removably connected between the lens unit andthe main body 61. An embodiment in which propriety is checked by adeterminer in an accessory device is hereinafter described.

In FIG. 6, another preferred camera system 70 is depicted, and includesa camera main body 71 and a lens unit 72. An image shake correctingdevice or module 73 as accessory device or attachment is removablysecured between the main body 71 and the lens unit 72.

The main body 71 is structurally the same as the main body 11. The lensunit 72 does not have the determiner 44 as included in the lens unit 12.An RFID tag or IC tag 75 is incorporated in the lens unit 72. Lens unittype data is stored in the RFID tag 75 for a lens unit type of the lensunit 72. The RFID tag 75 is structurally the same as the RFID tag 50.

The image shake correcting device 73 includes an accessory controller76, a memory 77, an image shake correcting circuit 78, an RFID tagreader 79 as first reception unit, a determiner 80, communicationcontacts 81 and 82, a communication interface 83 astransmission/reception unit, and a transmission/reception unit 84 orcommunication interface. The accessory controller 76 controls variouselements in the image shake correcting device 73.

A control program is stored in the memory 77 for control of elements inthe image shake correcting device 73. The accessory controller 76controls according to the control program read from the memory 77.

The image shake correcting circuit 78 subjects image data from the lensunit 72 to image shake correction. Also, the RFID tag reader 79 as aninterface for reception receives the lens unit type data from the RFIDtag 75 in the lens unit 72.

A reference data table is stored in the determiner 80 for propriety ofplural lens units. The determiner 80 evaluates the lens unit type datareceived by the RFID tag reader 79 with the reference data table, sopropriety between the lens unit 72 and the image shake correcting device73 is evaluated.

The contacts 81 connect with the contacts 16 a when the image shakecorrecting device 73 is loaded with the lens unit 72. The contacts 82connect with the contacts 36 when the main body 71 is loaded with theimage shake correcting device 73.

The accessory controller 76 controls the communication interface 83 fortransmitting and receiving data between the lens unit 72 and the imageshake correcting device 73. The accessory controller 76 controls thetransmission/reception unit 84 for transmitting and receiving databetween the main body 71 and the image shake correcting device 73.

A flow in FIG. 7 is referred to now, to describe operation of the camerasystem 70. When the image shake correcting device 73 is set on the mainbody 71, the accessory controller 76 checks existence or lack of settingof the lens unit 72. To this end, reception or lack of reception of thelens unit type data is checked according to the RFID tag reader 79.

If no lens unit 72 is found loaded, then the accessory controller 76causes the transmission/reception unit 84 to transmit data of lack ofthe lens unit to the main body 11 through the contacts 82 and 36. Themain body controller 30, upon reception of the data with thetransmission/reception unit 84, drives the LCD 33 to display a warningmessage to encourage setting of the lens unit 72.

If the lens unit 72 is found loaded, then the determiner 80 checkspropriety between the lens unit 72 and the image shake correcting device73 according to the lens unit type data received by the RFID tag reader79.

If impropriety is found between the lens unit 72 and the image shakecorrecting device 73, then the accessory controller 76 causes thetransmission/reception unit 84 to transmit data of the impropriety tothe main body 71. The transmission/reception unit 38 at the main bodycontroller 30 receives the data of the impropriety, so the main bodycontroller 30 drives the LCD 33 to display a warning message ofimpropriety between the lens unit 72 and the image shake correctingdevice 73. Also, a message of restricting performance of photography canbe displayed without a warning message.

If the lens unit 72 is found appropriate for the image shake correctingdevice 73, then the accessory controller 76 causes thetransmission/reception unit 84 to transmit the data of being appropriateto the main body 71. Then the main body controller 30, upon receivingthe data of being appropriate at the transmission/reception unit 38,allows the camera system to photograph an image normally withoutrestriction.

In the above embodiment, propriety between the lens unit and theaccessory device is checked. However, another preferred embodiment has adeterminer which checks propriety between a lens unit, an accessorydevice, and a camera main body.

In FIG. 8, still another preferred camera system 90 is illustrated, andincludes a camera main body 91 and a lens unit 92. An image shakecorrecting device or module 93 as accessory device or attachment isfitted between the main body 91 and the lens unit 92 in a removablemanner.

The main body 91 is structurally the same as the main body 71. Elementssimilar to those of the above embodiments are designated with identicalreference numerals. The lens unit 92 is structurally the same as thelens unit 72. See the description above.

A determiner 95 is included in the communication interface 83 unlike thedeterminer 80 in the image shake correcting device 73. A reference datatable is stored in the determiner 95 for propriety between the lens unitand the camera main body. When the RFID tag reader 79 receives the lensunit type data and the camera main body type data, the RFID tag reader79 refers to the data table, to check propriety between the lens unit92, the image shake correcting device 93 and the main body 91. Forremaining portions, the image shake correcting device 93 has a similarstructure to that of the image shake correcting device 73. Elementssimilar to those of the above embodiment are designated with identicalreference numerals.

The operation of the camera system 90 is described by referring to theflow in FIG. 9. When the main body 91 is loaded with the image shakecorrecting device 93, the accessory controller 76 checks existence orlack of the lens unit 92 on the image shake correcting device 93. Tothis end, it is determined whether lens unit type data is received ornot by the RFID tag reader 79.

If no setting of the lens unit 92 is found, then the accessorycontroller 76 causes the transmission/reception unit 84 to transmit dataof lack of the lens unit 92 to the main body 91 by use of the contacts36 and 82. When the main body controller 30 receives the data of thelack of the lens unit 92, then the main body controller 30 drives theLCD 33 to display a warning message for encouraging setting of the lensunit 92.

If the lens unit 92 is found loaded, then the determiner 95 evaluatesthe lens unit type data from the RFID tag reader 79 by referring to thereference data table, to check propriety between the lens unit 92 andthe image shake correcting device 93.

If the lens unit 92 is found not appropriate for the image shakecorrecting device 93, then the accessory controller 76 causes thetransmission/reception unit 84 to transmit data of impropriety to themain body 91. The main body controller 30, upon receiving the data ofthe impropriety at the transmission/reception unit 38, drives the LCD 33to display the warning message that the lens unit 92 is not appropriatefor the image shake correcting device 93. Note that other messages maybe indicated besides the warning message, for example, a message thatrestriction will occur in the performance of photographing.

If the lens unit 92 is found appropriate for the image shake correctingdevice 93, the determiner 95 evaluates the camera main body type datafrom the RFID tag reader 79 accessing the RFID tag 65 and the referencedata table; to check propriety between the main body 91 and the imageshake correcting device 93.

If the image shake correcting device 93 is found not appropriate for themain body 91, then the accessory controller 76 causes thetransmission/reception unit 84 to transmit data of no propriety to themain body 91. The main body controller 30, upon receiving the data,drives the LCD 33 to display a warning message of impropriety betweenthe main body 91 and the image shake correcting device 93. Also, othermessages may be indicated besides the warning message, for example, amessage that restriction will occur in the performance of photographing.

If the image shake correcting device 93 is found appropriate for themain body 91, the accessory controller 76 causes thetransmission/reception unit 84 to transmit data of propriety to the mainbody 91. The main body controller 30, upon receiving the data ofpropriety, controls for operation of the lens unit 92 and the imageshake correcting device 93.

In the present and above embodiments, the accessory device is the imageshake correcting device 93. However, any of various examples may becombined as an accessory device, such as an HDD unit, a stereo unit andthe like. Also, the lens unit 92 can be a type without a CCD. Anaccessory device may be a conversion lens device or other opticalattachment.

In the above embodiment, a radio wave is used for wireless communicationof data between RFID tags. However, data can be transmitted and receivedon line by use of signal lines connecting interfaces.

An image pickup element or photographing device for use in the inventionmay be any type other than CCD, for example, a CMOS image sensor.

Although the lens unit of the above embodiments includes the imagepickup element, a lens unit of the invention may be an interchangeablelens without the image pickup element. Furthermore, a camera of theinvention may be a camera distinct from a digital still camera, forexample, can be a video camera, a camera for use with silver halidephoto film, and also a camera for a specific use.

According to the preferred embodiments, propriety of setting theaccessory device, lens unit, and camera main body is determinedaccording to types. However, serial numbers of accessory device, lensunit, and camera main body may be used for determining propriety ofthose being set, because originally predetermined to include informationof their types. Although the accessory type data, lens unit type data,and camera main body type data are used in the above embodiments, yetaccessory device data, lens unit data, and camera main body dataaccording to the invention may be serial number data of accessorydevice, lens unit, and camera main body.

Although the present invention has been fully described by way of thepreferred embodiments thereof with reference to the accompanyingdrawings, various changes and modifications will be apparent to thosehaving skill in this field. Therefore, unless otherwise these changesand modifications depart from the scope of the present invention, theyshould be construed as included therein.

1. A camera system including a lens unit having a photographing lens,and a camera main body on which said lens unit is secured removably,wherein an accessory device is settable on a selected one of said mainbody and said lens unit, said camera system comprising: (A) said lensunit including: a first reception unit for receiving accessory devicedata from said accessory device; a determiner for checking whether saidaccessory device is appropriate for said lens unit or said main bodyaccording to accessory device data received by said first receptionunit, and for producing checking information; and a transmission unitfor transmitting said checking information; (B) said main body includinga second reception unit for receiving said checking information fromsaid lens unit.
 2. A camera system as defined in claim 1, wherein saidaccessory device data is accessory type data of a type of said accessorydevice.
 3. A camera system as defined in claim 1, wherein said main bodyincludes: an alarm device for outputting alarm information; and a mainbody controller for driving said alarm device if said checkinginformation represents that said accessory device is inappropriate.
 4. Acamera system as defined in claim 3, wherein said second reception unitis connected with said transmission unit by connection between contacts,and detects whether said lens unit is set on said main body.
 5. A camerasystem as defined in claim 4, wherein said alarm device includes adisplay panel for visibly outputting said alarm information.
 6. A camerasystem as defined in claim 1, wherein said first reception unit furtherreceives camera main body data from said main body; said determinerchecks whether a combination of said lens unit, said accessory deviceand said main body is appropriate.
 7. A camera system as defined inclaim 1, wherein said accessory device includes a first RFID tag forstoring said accessory device data; said first reception unit includesan RFID tag reader for wireless reception.
 8. A camera system as definedin claim 7, wherein said main body includes a second RFID tag forstoring camera main body data; said RFID tag reader further reads saidmain body data from said second RFID tag.
 9. A camera system as definedin claim 1, wherein said accessory device is a conversion lens device ora flash device.
 10. A lens unit having a photographing lens, and beingsecured removably to a camera main body to constitute a camera system,wherein an accessory device is settable on said camera system, said lensunit comprising: a reception unit for receiving accessory device datafrom said accessory device; a determiner for checking whether saidaccessory device is appropriate for said camera system according toaccessory device data received by said reception unit, and for producingchecking information; and a transmission unit for transmitting saidchecking information to said main body.
 11. A lens unit as defined inclaim 10, further comprising an image pickup element for photographingan object image by receiving light from said photographing lens.
 12. Alens unit as defined in claim 10, wherein said accessory device includesan RFID tag for storing said accessory device data; said reception unitincludes an RFID tag reader for wireless reception.
 13. A camera systemincluding a lens unit having a photographing lens, a camera main body onwhich said lens unit is secured removably, and an accessory devicesecured between said main body and said lens unit, said camera systemcomprising: (A) said accessory device including: a first reception unitfor receiving lens unit data from said lens unit; a determiner forchecking whether said lens unit is appropriate according to lens unitdata received by said first reception unit, and for producing checkinginformation; and a transmission unit for transmitting said checkinginformation; (B) said main body including a second reception unit forreceiving said checking information from said accessory device.
 14. Acamera system as defined in claim 13, wherein said main body includes:an alarm device for outputting alarm information; and a main bodycontroller for driving said alarm device if said checking informationrepresents that said accessory device is inappropriate.
 15. A camerasystem as defined in claim 14, wherein said second reception unit isconnected with said transmission unit by connection between contacts,and detects whether said accessory device is set on said main body. 16.A camera system as defined in claim 15, wherein said alarm deviceincludes a display panel for visibly outputting said alarm information.17. A camera system as defined in claim 13, wherein said first receptionunit further receives camera main body data from said main body; saiddeterminer checks whether a combination of said lens unit, saidaccessory device and said main body is appropriate.
 18. A camera systemas defined in claim 13, wherein said accessory device includes a firstRFID tag for storing said lens unit data; said first reception unitincludes an RFID tag reader for wireless reception.
 19. A camera systemas defined in claim 18, wherein said main body includes a second RFIDtag for storing camera main body data; said RFID tag reader furtherreads said main body data from said second RFID tag.
 20. A camera systemas defined in claim 18, wherein said lens unit includes a firstcommunication contact; said accessory device includes a secondcommunication contact, connected with said first communication contactby securing said lens unit, for detecting whether said lens unit is set.21. A camera system as defined in claim 13, wherein said lens unitfurther includes an image pickup element for photographing an objectimage by receiving light from said photographing lens.
 22. A camerasystem as defined in claim 13, wherein said accessory device is an imageshake correcting device.
 23. An accessory device for being securedbetween a camera main body and a lens unit having a photographing lensand being secured to said main body removably, said accessory devicecomprising: a reception unit for receiving lens unit data from said lensunit; a determiner, for checking whether said lens unit is appropriateaccording to lens unit data received by said reception unit, and forproducing checking information; and a transmission unit for transmittingsaid checking information to said main body.
 24. An accessory device asdefined in claim 23, wherein said lens unit includes an RFID tag forstoring said lens unit data; said reception unit includes an RFID tagreader for wireless reception.